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var symbols = [
Symbol(), Symbol("iterator"), Symbol.for("iterator"), Symbol.iterator
];
for (var sym of symbols) {
var key = {
toString() { return sym; }
};
// Test that ToPropertyKey can return a symbol in each of the following
// contexts.
// Computed property names.
var obj = {[key]: 13};
var found = Reflect.ownKeys(obj);
assertEq(found.length, 1);
assertEq(found[0], sym);
// Computed accessor property names.
var obj2 = {
get [key]() { return "got"; },
set [key](v) { this.v = v; }
};
assertEq(obj2[sym], "got");
obj2[sym] = 33;
assertEq(obj2.v, 33);
// Getting and setting properties.
assertEq(obj[key], 13);
obj[key] = 19;
assertEq(obj[sym], 19);
(function () { "use strict"; obj[key] = 20; })();
assertEq(obj[sym], 20);
obj[key]++;
assertEq(obj[sym], 21);
// Getting properties of primitive values.
Number.prototype[sym] = "success";
assertEq(Math.PI[key], "success");
delete Number.prototype[sym];
// Getting a super property.
class X {
[sym]() { return "X"; }
}
class Y extends X {
[sym]() { return super[key]() + "Y"; }
}
var y = new Y();
assertEq(y[sym](), "XY");
// Setting a super property.
class Z {
set [sym](v) {
this.self = this;
this.value = v;
}
}
class W extends Z {
set [sym](v) {
this.isW = true;
super[key] = v;
}
}
var w = new W();
w[key] = "ok";
assertEq(w.self, w);
assertEq(w.value, "ok");
assertEq(w.isW, true);
// Deleting properties.
obj = {[sym]: 1};
assertEq(delete obj[key], true);
assertEq(sym in obj, false);
// LHS of `in` expressions.
assertEq(key in {iterator: 0}, false);
assertEq(key in {[sym]: 0}, true);
// Methods of Object and Object.prototype
obj = {};
Object.defineProperty(obj, key, {value: "ok", enumerable: true});
assertEq(obj[sym], "ok");
assertEq(obj.hasOwnProperty(key), true);
assertEq(obj.propertyIsEnumerable(key), true);
var desc = Object.getOwnPropertyDescriptor(obj, key);
assertEq(desc.value, "ok");
}
reportCompare(0, 0);
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